Pocket calculator



March 28, 1961 w. A. REID POCKET CALCULATOR 2 Sheets-Sheet 1 Filed Oct.16, 1957 Will ie Jifieid INVENTOR ATTORNEYS March 28, 1961 W. A- REIDPOCKET CALCULATOR Filed Oct. 16, 1957 2 Sheets-Sheet 2 I L m'l t 20 /Z I/7 J W/LL/5 q.PE/D

INVENTOR I I BY I ATTORNEYS United States Patent POCKET CALCULATORWillie A. Reid, South San Francisco, Calif. (19426 C St., Chowchilla,Calif.)

Filed Oct. 16, 1957, Ser. No. 690,497 Claims. (Cl. 235-67) Thisinvention relates to a pocket calculator, and has as its primary objectthe provision of a device which is small and compact and which may bereadily carried in the pocket, which provides a very accurate means forrapid addition, subtraction, multiplication, and division of numericalquantities.

A further object of the invention is the provision of a device of thischaracter which is extremly accurate, and which may be readily adjusted,to provide a variety of substantially immediate answers to arithmeticalproblems.

A still further object of the invention is the provision of a devicewhich is characterized by extreme simplicity in construction, andreliability of operation.

Still another object of the invention is the provision of a device ofthis character provided with a pair of transparent concentric cylinders,with a third concentric cylinder carried interiorly of the other two,and suitable indicia carried by certain of these cylinders, togetherwith slide means movable upon relative rotation of the cylinders to eachother, whereby the positioning of the slides movable by one of saidcylinders in relation to their associated indicia, may be used toperform mathematical computations.

A further object of this invention is the provision of a device of thischaracter which is sturdy and durable in construction, reliable andeflicient in operation, relatively simple and inexpensive tomanufacture, simple to utilize.

Still other objects will in part be obvious, and in part be pointed out,and shown in the accompanying drawings, wherein:

Figure 1 is a side elevational view of one form of the device embodyingfeatures of the instant invention, the indicia being omitted, and theouter transparent cylinder being shown without its visible underlyingcomponents, which will be illustrated more fully in subsequent drawings.

Fig. 2 is a view showing the outer transparent cylinder in section, andshowing the outside of the intermediate threaded cylinder.

Fig. 3 is a sectional view, taken substantially along the center line 33of Fig. 1.

Fig. 4 is a sectional view taken substantially along the section line4-4 of Fig. 3.

Fig. 5 is a sectional view taken substantially along the section line5-5 of Fig. 3.

' Fig. 6 is an enlarged detail view of the left end of the calculator asshown in Fig. 1, with the outer cylinder broken away to show the indiciacylinder.

Fig. 7 is an enlarged fragmentary detail view showing parts of the threecylinders illustrated in Fig. 2 on an enlarged scale; and

Fig. 8 is a detail sectional view taken on the section line 8-8 of Fig.7.

Similar reference characters refer to similar parts throughout theseveral views of the drawing.

Having reference now to the drawings in detail, there is shown at 10 atransparent outer cylinder, which is on the intermediate provided on itsinner side with a pair of parallel ridges 11-11 forming a spline, asbest shown in Figs. 4 and 5, which spline provides a guide for atransparent T-shaped slide 12, having a hair line at the center thereof.Mounted concentrically within the outer cylinder 10 there is anintermediate cylinder 13, which is also transparent, and is helicallythreaded both exteriorly and interiorly. The inner threads on thisintermediate cylinder 13 are designated by reference numeral 20 and theouter threads by the reference numeral 21. One end of the intermediatecylinder 13 has an enlarged head '14, which extends beyond the end ofthe outer cylinder 10, in order that the intermediate cylinder 13 may berotated relative to the outer cylinder 10.

interiorly, the head 14 contains an annular groove 15, for a retainingring 16, which is carried by an inner cylinder 17.

The slide 12 guided by the spline 11 is adapted to be engaged by theouter threads 21 of the intermediate cylinder 13, whereby rotation ofthe head 14 will occasion relative movement of the slide 12 along thelength of the outer cylinder 10.

The inner cylinder 17 also has therein a slot or channel 18, in which aslide or key 19 is mounted, which latter is adapted to be engaged by theinner threads 20 of the intermediate cylinder 13. The guideway 18 isnormally aligned with the spline 11, so that the two slides 12 and 19are normally in position to be read along the same line of sight.

The end of inner cylinder 17 opposite the flange 16 carries a circularhead 22, which corresponds in diameter to the outer diameter of thesleeve 10.

The slide 19 also carries a hair line, which may be correlated withsuitable indicia on either the number 13 or the inner cylinder 17.

The inner cylinder 17 may be open at either or both ends, in order toprovide space for data-carrying sheets, or similar articles.

From the foregoing, the operation of the device should now be readilyapparent. The inner and outer cylinders 17 and 10, respectively, arenormally stationary relative to each other, while the internally andexternally threaded intermediate cylinder 13 is rotatable relative toboth. Upon holding of the outer cylinder 10, and the disc 22 theenlarged head 14 may be rotated, to rotate the intermediate cylinder 13and, by virtue of the threaded engagement previously described, move theslide 12 to any desired position.

Correspondingly, by holding the outer cylinder 10 and the head 14simultaneously, rotation of the disc 22 on the inner cylinder 17 willcause corresponding movement of the slide 19 to any desired location.

The threads of the intermediate cylinder course, be of any desiredpitch, but it has that four turns per inch are desirable. or indicia mayalso take any desired preferred embodiment of the invention have thelogarithms of numbers placed on the left side 23 of the thread 21' ofthe intermediate cylinder 13. A zero is placed as near the disc 22 aspossible and the first logarithm is placed one millimeter from the zeroand thereafter they are spaced one millimeter apart continuing in aclockwise direction around the intermediate cylinder 13.

The real numbers are placed on the right side 24 of the thread 21 anddirectly opposite their respective logarithms, as clearly shown in Fig.6 of the drawings.

In the use and operation of the device, when it is desired to addcertain numbers, the enlarged head 14 is held and the disc 22 is rotateduntil the hair line on the slide 19 is positioned at the zero indicia.

13 may, of been found The calibrations form, and in a- Then theintermediate cylinder 13 and inner cylinder 17 are held simultaneouslyagainst rotation, while the transparent cylinder is rotated until thehair line on the slide 12 is positioned at the number to which anothernumber is to be added.

The outer transparent cylinder 10 and the disc 22 are is moved over theminuend. Then, with the outer trans parent cylinder 10 and the innercylinder 17 held against rotation, the enlarged head 14 is rotated untilthe hair line on the slide 19 is at the subtrahend. The difference willbe indicated under the hair line on the slide 19.

In the above mentioned operations, thelogarithmic numbers will be usedfor multiplying and dividing, while the real numbers are used inaddition and subtraction.

From the foregoing, it will now be seen that there is herein provided animproved pocket calculator, which accomplishes all of the objects ofthis invention, and others, and one having many advantages of greatpractical utility and commercial importance.

4 As many embodiments may be made of this inventive concept, and as manymodifications may be made in the embodiment hereinbefore shown anddescribed, it is to be understood that all matter herein is to beinterpreted merely as illustrative and not in a limiting sense.

What I claim as my invention is:

1. In a pocket calculator of the class described, the combination of atransparent outer cylinder having internal longitudinally positionedridges therein forming a guide spline, an intermediate transparentcylinder threaded externally and internally having pairs of parallelrows of indicia around its outer circumference with each pair comprisedby a series of real numbers and a series of aligned logarithmic numberspositioned within the outer cylinder, an indicating slide movable in theguide spline on the outer cylinder and engaged between the externalthreads on the intermediate cylinder, an inner cylinder having alongitudinally positioned guide in its external surface positionedwithin the intermediate cylinder, a second slide positioned in saidguide in the inner cylinder and engaged between the internal threads onthe intermediate cylinder, and means for rotating each of said cylindersrelatively to the others to translate the relative positions of saidslides and move the latter into aligned positions with said rows ofindicia. I

2. In a pocket calculator of the class described, the combination of atransparent outer cylinder having internal longitudinally positionedridges therein forming a guide spline, an intermediate transparentcylinder threaded externally and internally having pairs of parallelrows of indicia around its outer circumference with each pair comprisedby a series of real numbers and a series of logarithmic numberspositioned within the first cylinder, an indicating slide movable in theguide'spline on the outer cylinder and engaged between the externalthreads on the intermediate cylinder, an inner cylinder having alongitudinally positioned guide in its external surface positionedwithin said intermediate cylinder, a second slide positioned in saidguide in the inner cylinder and engaged between the internal threads onthe intermediate cylinder, an enlarged head on said intermediatecylinder positioned beyond one end of the outer cylinderfor rotating theintermediate cylinder relatively to the outer cylinder to translate thesecond slide with respect to the first slide and align said second slidewith said rows of indicia, and a disc on said inner cylinder positionedbeyond the other end of the outer cylinder for rotating the said innercylinder relatively to the outer and intermediate cylinders to translatethe first slide with respect to the second slide and align saidifirstslide with said rows of indicia.

3. In a pocket calculator of the class described, the combination of atransparent outer cylinder having internal longitudinally positionedridges therein forming a guide spline, an intermediate transparentcylinder threaded externally and internally having pairs of parallelrows of indicia around its outer circumference with each pair comprisedby a series of real numbers and a series of longitudinally alignedlogarithmic'numbers positioned within the first cylinder, an indicatingslide movable in the guide spline on the outer cylinder and engagedbetween the external threads on the intermediate cylinder, an innercylinder having a longitudinally poistioned guide a in its externalsurface positioned within said intermediate cylinder, a second slidepositioned in said guide in the inner cylinder and engaged between theinternal threads on the intermediate cylinder, an enlarged head having adiameter approximately equal to that of the outer cylinder on saidintermediatercylinder positioned beyond and adjacent one end of theouter cylinder for rotating the intermediate cylinder relatively to theouter cylinder to translate the second slide with respect to the firstslide and align said second slide with said rows of indicia,

and a disc also having a diameter approximately equal to that of theouter cylinder on said inner cylinder positioned beyond and adjacent theother end of the outer cylinder for rotating the said inner cylinderrelatively to the outer and intermediate cylinders to translate thefirst slide with respect to the second slide and align said first slidewith said rows of indicia.

4. In a pocket calculator of the class described, the combination of atransparent outer cylinder having internal longitudinally positionedridges therein forming a guide spline, an intermediate transparentcylinder threaded externally and internally having pairs of parallelrows of indicia around its outer circumference with each pair comprisedby a series of real numbers and a series of longitudinally alignedlogarithmic numbers positioned within the first cylinder, a transparentindicating slide having a hair line therein positioned in said guide inthe inner cylinder and engaged between the internal threads on theintermediate cylinder, an enlarged head having a diameter approximatelyequal to that of the outer cylinder on said intermediate cylinderpositioned beyond and adjacentone end of the outer cylinder for rotatingthe intermediate cylinder relatively to the outer cylinder to translatethe second slide with respect to the first slide and align the hair lineon said second slide with said rows of'indicia, and a disc also having adiameter approximately equal to that of the outer cylinder on said innercylinder poistioned beyond and adjacent the other end of the outercylinder for rotating saidinner cylinder rela tively to the outer andintermediate cylinders to translate the first slide with respect to thesecond slide and align the hair line on said first slide with. said rowsof indicia.

5. In a pocket calculator of the class described, the combination of atransparent outer cylinder having internal longitudinal ridges thereinforming a guide spline, an intermediate transparent cylinder threadedexternally and internally having pairs of parallel rows of indiciaaround its outer circumference with each pair comprised by a series ofreal numbers and a series of aligned logarithmic numbers positionedwithin the first cylinder, an indicating slide movable in the guidespline on the outer cylinder and engaged between the external threads.

on the intermediate cylinder, an inner cylinder having a central bore.serving as a receptacle for carrying associated data sheets or the likeand having a longitudinallypositioned guide in its external surfacepositioned within said intermediate cylinder, a second slide positionedin said guide in the inner cylinder and engaged between the internalthreads on the intermediate cylinder, an enlarged head having ardiameterapproximately equal to that of the outer cylinder on said intermediatecylinder positioned beyond and adjacent one end of the'outer cylinderfor rotating the intermediate cylinder relatively to the outer cylinderto translate the second slide with respect to the first slide and alignsaid second slide with said rows of indicia, and a disc also having adiameter approximately equal to that of the outer cylinder on said innercylinder positioned beyond and adjacent the other end of the outercylinder for rotating the said inner cylinder relatively to the outerand intermediate cylinders to translate the first slide with respect tothe second slide and align said first slide with said rows of indicia.

References Cited in the file of this patent UNITED STATES PATENTSFOREIGN PATENTS Great Britain May 12, 1921

